I use Arch Linux, which if I remeber correctly installs python3 and not python2 by default. Let’s check.

❯ python --version
Python 3.3.5

Yep. If we also look at the path jekyll is spitting out in that error message /usr/bin is in there, which is where python3 resides. My guess is if we install python2 it’ll be put in /usr/bin as well. Then if we run jekyll again, it’ll check that directory, find python2, and be happy.